[#1078] use SOLR data_dict instead of package_dictize when possible

This work is ongoing, please leave this PR open for now.  Comments welcome.

Performance numbers so far, taking best of 10 runs for each:

option | time(s) | improvement
--- | ---: | ---:
original | 0.158 | 1.0x
53a4e5c | 0.130 | 1.22x